building a dynamometer test-stand

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Building a dynamometer test-stand Dortland, A.E. Published: 01/01/2007 Document Version Publisher’s PDF, also known as Version of Record (includes final page, issue and volume numbers) Please check the document version of this publication: • A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication Citation for published version (APA): Dortland, A. E. (2007). Building a dynamometer test-stand. (DCT rapporten; Vol. 2007.134). Eindhoven: Technische Universiteit Eindhoven. General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Download date: 29. Jan. 2018

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Page 1: Building a dynamometer test-stand

Building a dynamometer test-stand

Dortland, A.E.

Published: 01/01/2007

Document VersionPublisher’s PDF, also known as Version of Record (includes final page, issue and volume numbers)

Please check the document version of this publication:

• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differencesbetween the submitted version and the official published version of record. People interested in the research are advised to contact theauthor for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers.

Link to publication

Citation for published version (APA):Dortland, A. E. (2007). Building a dynamometer test-stand. (DCT rapporten; Vol. 2007.134). Eindhoven:Technische Universiteit Eindhoven.

General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright ownersand it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.

• Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ?

Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediatelyand investigate your claim.

Download date: 29. Jan. 2018

Page 2: Building a dynamometer test-stand

Building a dynamometer test-stand

TU/e Masters Internship Report

Building a dynamometer test-standA.E. Dortland (534008)

22nd October 2007Report no: DCT-2007-134

Supervisors

Prof. ir. A.A. Frank M. Sc. Ph.D.(UC Davis)dr. P.A. Veenhuizen (TU/e)

Eindhoven University of Technology University of California, DavisDepartment of Mechanical Engineering Department of Mechanical EngineeringDivision Dynamical Systems Design Hybrid Electrical Vehicle CenterMaster track Automotive Engineering Science

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Contents

1 Summary 5

2 Introduction 7

3 ChallengeX 9

3.1 Well to wheel petrolium use . . . . . . . . . . . . . . . . . . . . . 9

4 Trinity 11

4.1 Driving modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

4.2 Electric motor and battery efficiency . . . . . . . . . . . . . . . . 12

4.3 CVT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

4.3.1 CVT chain . . . . . . . . . . . . . . . . . . . . . . . . . . 15

4.3.2 CVT hydraulics . . . . . . . . . . . . . . . . . . . . . . . . 15

4.3.3 CVT Control . . . . . . . . . . . . . . . . . . . . . . . . . 17

5 Prius engine 23

5.1 Why using ethanol . . . . . . . . . . . . . . . . . . . . . . . . . . 23

5.2 Adjustments on the engine . . . . . . . . . . . . . . . . . . . . . 24

6 Dynamometer test stand 25

6.1 Brackets and shafts . . . . . . . . . . . . . . . . . . . . . . . . . . 25

6.1.1 Engine mounting brackets . . . . . . . . . . . . . . . . . . 27

6.1.2 Dynamometer mounting brackets . . . . . . . . . . . . . . 30

6.1.3 Dynamometer adaptor plate . . . . . . . . . . . . . . . . . 32

6.1.4 Flywheel adaptor shaft . . . . . . . . . . . . . . . . . . . . 33

6.2 Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

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6.2.1 Engine controls . . . . . . . . . . . . . . . . . . . . . . . . 35

6.2.2 Engine cooling . . . . . . . . . . . . . . . . . . . . . . . . 37

6.3 Dynamometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

6.3.1 Hydraulic system of the dynamometer . . . . . . . . . . . 38

6.3.2 Controlling the dynamometer . . . . . . . . . . . . . . . . 40

6.4 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

7 Conclusion 41

A Symbols 43

B Derivation of the acceleration of the drive shaft 45

C Engine harness 47

D Technical drawings 49

D.1 Dynamometer adaptor plate part 1 . . . . . . . . . . . . . . . . . 49

D.2 Dynamometer adaptor plate part 2 . . . . . . . . . . . . . . . . . 51

D.3 Flywheel adaptor shaft . . . . . . . . . . . . . . . . . . . . . . . . 52

D.4 Encoder adaptor plate . . . . . . . . . . . . . . . . . . . . . . . . 53

D.5 Front engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

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Chapter 1

Summary

The mechanical engineering department of the University of California Davishas a very progressive team working on plug-in hybrid vehicles. For severalyears they have been participating in different competitions for hybrid vehi-cles. The last three years they were re-engineering a Chevrolet Equinox forthe General Motors competition ’Challenge X’. Last year’s competition weekwas a good week for UC Davis. The car showed a much better fuel economywhile improving the performance. A very important part of the car is a custombuilt Continuous Variable Transmission. Professor Frank invented a new con-trol strategy for this CVT. A simulink model shows the main idea behind thiscontrol strategy. Another important part of the car is the engine. The team,Team Fate, decided to use a Toyota Prius engine (Atkinson cycle) and to runthis engine on E85(ethanol). This engine helps to build a more sustainable car.However the fuel economy is improved the engine was not tuned to burn E85.The most important purpose of the powertrain and its control strategy is torun the engine on the Ideal Operating Line. To achieve this some knowledgeabout the engine which burns ethanol is necessary. A dynamometer stand forthe engine to obtain an engine map was built. Unfortunately this is not finishedyet but a lot of work is already been done.

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Chapter 2

Introduction

For several years the mechanical engineering department of the University ofCalifornia Davis have been building hybrid electric vehicles. Mainly volunteersare working in Team Fate. The team, lead by Professor Frank, builds cars withmuch better fuel economy than conventional vehicles. Last year was the thirdyear Team Fate participated in a General Motors hybrid vehicle competitioncalled Challenge X. The last weeks before the assessment in Detroit a lot ofwork was done on the car to get it operational. After the competition theteam started optimizing the car. This report first describes, in chapter three,what this competition is about and reveals the own goals of the team. Chapterfour is about the car involved in this competition. The drivetrain topology willextensively be explained. Different aspects of the transmission, a custom builtCVT and heart of the drivetrain, will be discussed. A control strategy for thisCVT, invented by Professor Frank, is implemented in Matlab. Some simulationsare done and results will be shown. Chapter five is about the used engine andfuel: A prius engine which burns ethanol. The last chapter is about the actualassignment of this internship: Building a test stand for the mentioned engine.This test stand should provide data about the characteristics of the engineburning ethanol. During the internship the car is extensively tested by GM inDetroit. Some good results were achieved but the engine was not yet tunedfor ethanol so there is still room to increase fuel economy of the car. This teststand is the first step to make this possible.

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Chapter 3

ChallengeX

ChallengeX is the name of the competition where UC Davis is involved intogether with 16 other American universities. The challenge is to re-engineera General Motors Chevrolet Equinox to obtain energy sustainability, reduceemissions and greenhouse gases while maintaining or exceeding the vehicle’sutility and performance. The hybrid electric vehicle competition holds 4 years:The first year the teams had to focus on modeling, simulation and testing ofthe vehicle powertrain and vehicle subsystems selected by the university. UCDdecided to build a pre-transmission parallel plug-in hybrid. The judges werepositive about the work done by Team Fate, so GM donated a car to UCD toapply their plan. Year 2 and 3 required the teams to integrate their powertrainand subsystems in the donated GM Equinox. After each year the teams haveto come together to present their cars to a panel of judges. Several eventswill test fuel economy, emissions, vehicle utility and performance. Year 2 wasdisappointing because the car of UCD was unable to drive at the start of thecompetition due to several issues. Fortunately the car drove the last day ofthe competition. After year 3 the car must be in showroom condition. Afterhard work the car was running. Unfortunately there was not enough time leftto finish the interior of the car. But the main goal is achieved: Better fueleconomy and improved performance. Year 4’s competition will be a long drive.No decision is made yet where this event will take place.

UCD tries to go a step further than the goals of Challenge X: They like to builta vehicle which only uses renewable energy. One of the events in Challenge Xis the ’Well to wheel’ event and this is UCD’s most important event.

3.1 Well to wheel petrolium use

The ’Well to wheel’ event looks at the total energy use of a car. Losses in everystep to get the energy to the the wheel will be taken into account. Energyuse will be calculated as an equivalent of petroleum usage. There are severalopportunities to get energy from different sources to the wheels. The idea of

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Figure 3.1: Stock Chevrolet Equinox 2005

UCD Davis is to transfer this energy as efficient as possible and maybe moreimportant: make use of renewable sources. The idea behind this plug in hybridis based on the use of solar panels: People can install a solar panel on theirroof. In one day you can collect enough solar power to charge the battery of thecar during the night. The next day the car can drive 40 miles all electric. Thisis 15 miles more than the average American person drives per day. So, most ofthe days you can drive your car for free without emissions. Of course the solarpanel is not free, but in five years you will earn the money back because youdon’t have to buy gasoline. Since an average solar panel will last 30 years, thenext 25 years your energy is free. When the batteries are discharged to about 20percent SOC the car will drive in hybrid mode. The engine will always operateon the ideal operating line and the electric motors will assist when necessary.This driving mode results in a much more efficient fuel use than a conventionalcar. For further decreasing emissions E85 is used as fuel. This year the teamwas more successful than last year and especially in the ’Well to wheel’ event.The team scored second on this event, with even more room for improvement,which will be discussed later.

Figure 3.2: ”Plug in to the sun”

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Chapter 4

Trinity

Trinity, the re-engineered vehicle, is a pre-transmission parallel plug-in hybrid.The heart of the power train is a custom built Continuous Variable Transmissiondesigned at UC Davis. This CVT will be extensively discussed in 4.3.3. Thecar is four-wheel driven: The front axle is driven by a Prius combustion engineand a 75kW permanent magnet electric motor. Both are connected to theinput shaft of the CVT. The rear axle is driven by a 60kW induction electricmotor. Electric energy is stored in a 15.6 kWh lithium-ion battery pack. Thispowertrain makes it possible that the vehicle performance and fuel economy ofTrinity is superior to the stock vehicle. Figure 4.1 shows a drawing with all themajor powertrain components.

Figure 4.1: Powertrain used in Trinity

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4.1 Driving modes

Trinity has several driving modes: It can operate all electric (charge depleting),charge sustaining and the so-called tow and four wheel mode. First of all thecar is designed in a way that an average American can drive an ordinary daywithout burning oil: There is an electric range of 40+ miles all electric. Whenthe batteries reach the state of charge of 20 percent the car switches into hybridmode. The car also switches to hybrid mode when the speed exceeds 60 mph,because the engine then operates in its most efficient spot. In case of all electricmode the car is powered by the two electric motors. Together they can provide135 kw. The front electric motor is used till it reaches its power limit, then therear electric motor will assist to fulfil the power command. The reason for usingthe total power of the front electric motor first is the higher efficiency. Thishigher efficiency is a result of transmitting the torque through the cvt. The idealoperating line of the front electric motor will be used. Charge sustaining modestarts when the batteries have a state of charge of 20 percent. This will preventthe batteries from permanent damage. The engine is now the most importantpower source. The electric motors will only assist in case of high accelerationsand for low speeds when the engine will shut down. To keep the state of chargearound 20 percent the engine will deliver a little more power than necessaryto drive the vehicle. A negative torque will be applied to the front electricmotor to charge the batteries. When the batteries reach a given maximumstate of charge (around 22 percent) the negative torque will be stopped. Thisway the energy flow through the batteries is minimized. The batteries can befully charged by the grid, which is far more efficient. In the next section theefficiency losses of the battery will be pointed out.

4.2 Electric motor and battery efficiency

As mentioned before the energy flow through the batteries should be minimized.In every energy flow there are losses. The figures 4.2 and 4.4 in this sectionshow the difference between the motor efficiency with and without includingefficiency losses caused by the batteries. Figure 4.2 shows the motormap of aUnique Mobility 100kW motor. This motor is not the same motor as used inTrinity but a bigger version. For simulation this motor can be downsized butthat’s not necessary to show efficiency losses caused by batteries.

Motor efficiency is calculated as follows:

η =Tω

EbIb(4.1)

Motor efficiency including battery losses is calculated as follows:

η =Tω

EocIb=

(Eb + IbRb)Ib(4.2)

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Figure 4.2: Efficiency map electric motor

In the first situation the mechanical output power is divided by the batteryvoltage times the amount of amps. In the second situation the denominatoris represented by the open circuit voltage times the amount of amps. Thisvoltage is higher and will consequently result in a lower efficiency. In figure 4.3a diagram is drawn which shows the difference between the two voltages.

Figure 4.3: Electric diagram battery and motor

The battery resistance in trinity is approximately 0.1 ohm. Losses due to thisresistance result in an overall lower efficiency for the motor. A new motormap,including battery losses, is made. Figure 4.4 clearly shows the difference inefficiency between either taking battery losses into account or not.

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Figure 4.4: Efficiency map electric motor including battery losses

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4.3 CVT

The custom built CVT by UCD is different from the conventional CVT onseveral points. The used CVT in Trinity is a modified 2.0 L Jatco ContinuouslyVariable Transmission. The two main differences are the use of a chain insteadof a pushbelt and pulley actuation is done by servo pumps instead of an enginedriven pump. Next to these two differences the controls are done different too:instead of controlling R, Rdot is controlled. These three differences will bediscussed in the next sections.

4.3.1 CVT chain

A conventional CVT transmits torque from the primary pulley to the secondarypulley through a pushbelt. This pushbelt will slip what decreases the efficiency.In the CVT of UCD the belt is replaced by a chain. This chain has a highpower and torque capacity, high efficiency (up to 94.7 percent) and producesless noise. The chain is designed in a way that a linear motion of the chain itselfwill result in a curved motion on the surfaces on the sides of the chain where itinteracts with the pulleys. A rolling action between the pins of the chain takesplace without slipping with respect to the pulleys, what avoids wear [Bro]. Thechain is produced by a company from the Netherlands: Gear Chain Industries.Figure 4.5 shows the typical shape of the chain.

Figure 4.5: CVT chain by Gear Chain Industries

4.3.2 CVT hydraulics

The hydraulic system of the CVT is totally changed. In a conventional CVTan engine driven pump delivers the required pressure to clamp the belt andchange the ratio. Electronically controlled valves controle the pressure for bothpulleys. At high speeds the pressure developed exceeds the required pressure,so the pressure will be released. This pressure release contributes to losses. Themodified CVT uses high voltage servo hydraulic pumps for clamping pressure,pressure for drive ratio and lubrication. Although there is still a little leakage,

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losses are negligible compared to the conventional CVT. Calibration in this sys-tem is easy; There is a pressure feedback form pressure transducers. Figure 4.6shows the hydraulic diagram. The clamping pressure pump provides pressureto both pulleys. The shift pump only provides pressure to change the drivingratio.

Figure 4.6: Hydraulic diagram cvt

When the CVT case was totally machined by Team Fate members the hydrauliclines had to be fabricated. First of all pipes from the inputs in the CVT (primarypulley, secondary pulley and lubrication) to the NPT fittings in the case werefabricated. With a pipe bender stainless steel pipes were bent till they fitted inthe small available space. The pipes are mainly located in the sump. All theseparate lines were pressurized to see if there were no leakages. This was donewith a drill which spinned a pump. All of them could withstand the requiredpressure of 800 psi so the electric motor and the engine could be mountedto the CVT, which was already mounted on the subchassis. When the frontpowertrain was installed in the car the fabrication of hard -and softlines betweenthe CVT and the pumps could be started. Hard lines were used because it looksbetter under the car. Important was to use a little piece of softline because thepumps and the CVT can move with respect to each other; The pumps are rigidly

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mounted to the subchassis and the cvt can move with respect to the subchassis.The hardlines were made in the same way as the lines in the transmission itself.Figure 4.7 shows the pipes installed under the car.

Figure 4.7: Pipes and hoses for CVT

When everything was properly installed and tested a cover of sheet metal wasmade. This cover protects the powertrain from rocks and provides better aro-dynamica.

4.3.3 CVT Control

The powertrain and its controls determine how the vehicle responds to thedriver’s commands. In Trinity the CVT is controlled different from the stockCVT: By controlling the ratio rate of change, Rdot. The equation which de-scribes the dynamic behaviour of the CVT is as follows:

ωds =−RIeωe + RTe − Tdrag − Tlosses

IeR2 + Ids(4.3)

The derivation of this equation can be found in appendix B

This equation is implemented in Matlab/Simulink. After implementing thisequation the model can be extended with a step in speed or a driver’s cycle anda part of the used control strategy of Trinity. For better understanding of themodel a brief explanation of the control strategy is needed. The highest level ofcontrol strategy shows that the car will first deplete the batteries till a state ofcharge of 20 percent is reached. The engine will only fire up if the speed exceeds60 mph, below this speed the electric motors supply the power. When the SOCof 20 percent is reached the car will go into hybrid mode. This means that theengine will be the major powersource, however the acceleration from 0 to 15mph is done by the electric motors. When the car exceeds 15 mph the engine

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starts and will operate on the Ideal Operating Line. The electric motors willassist when necessary. In other words it will compensate for the lack of powerfor hard accelerations. Furthermore the front electric motor delivers energy tothe batteries while breaking; regenerative breaking. This is not possible at therear axle due to the use of overrunning clutches. These are built in to avoiddrag of the electric motor while not being used. The SOC will be kept around20 percent. The reason for this is already mentioned. As said, the dynamicequation is implemented in a simulink model. The inputs for this equation areR, Rdot and the engine torque. The other parameters of the equation will becalculated or are constants. Output of the equation is the angular accelerationof the drive shaft. From this acceleration the engine speed and vehicle speedcan be calculated. This will be the feedback signal of the model. A desiredvehicle speed is commanded. By subtraction the actual vehicle speed from thedesired vehicle speed an error is obtained. This error signal will be multipliedby a gain. The output value of this multiplication represents Rdot. Rdot willchange the input of the dynamic equation what will affect the drive shaft speed.The subsystem ’saturation’ avoids that the boundary values of R and Rdot willbe exceeded. The figures 4.8 and 4.9 show the model.

Figure 4.8: CVT model, commanding speed

The reason for using feedforward control is to avoid a short drop in speed whenthe driver wants to accelerate. This drop in speed is a consequence of the termwith Rdot. The negative sign before the Rdot term makes this term exactlythe opposite of what is desirable. A CVT which is only powered by an internalcombustion engine requires an increase in engine torque. In a hybrid vehiclethis drop in speed can be compensated by an electric motor. This model and amore extended model will show how to implement this.

A simulation with this model is done: A step in speed was commanded. Figure4.10 will show the result of a step in speed from 10 to 15 m/s.

The results show that in a reasonable time the speed of 15 m/s is achieved. Rdot

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Figure 4.9: Saturation of R and Rdot

Figure 4.10: Results CVT simulation, commanding speed

is positive at the moment the speed command increases. This is what normallyhappens in a CVT when an acceleration takes place. For this simulation aconstant engine torque was used. In the next model this will change.

The next step is to change into a model that is power commanded instead ofspeed commanded. The power commanded model is shown in figure 4.11 andfigure 4.12. The first figure represents block ’CVT’ from the second figure.Determining the desired power can be easily done by solving the equation forTrl. In the simulink model this is done in the block ’Road Load’.

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Trl = Rw(frmvg + 0.5rhoV 2v CwA + mva) (4.4)

This torque multiplied by the angular velocity of the wheels gives the desiredpower. This signal will be commanded to the closed loop system, which issituated in the CVT block. This block contains a subsystem with the CVTdynamics. These dynamics are the same as the first model. Also the saturationsubsystem is the same. Output signal of the dynamic model of the CVT isagain the angular velocity of the drive shaft. To obtain the input shaft angularvelocity of the engine and motor angular velocity, driveshaft velocity will bemultiplied by the ratio. In a look-up table a torque belonging to the engineor motor speed will be found. The feedback signal (the output power of theengine plus the power of the motor) will be provided by the multiplication ofthe engine and motor speed and the governing torque from the look up table.The model uses two look up tables: One for the engine and one for the electricmotor. For lower speeds the electric motor is used and when the speed exceeds15 mph the engine is started. Both look up tables should represent the IdealOperating Lines. Because the IOL of the electric motor is not available at thismoment a constant torque of 100 Nm is used. This can be easily changed in themodel when this information is available. Because the engine stays on the IOLthere will be a lack of power when a hard acceleration is required. The electricmotor will compensate for this lack of power: The power error in the modelis divided by the engine speed. This torque is added to the input shaft. Alsothe compensation for the Rdot term will be a torque input on the input shaft.These two compensations together is the electric motor torque, if the speed isabove 15 mph. Otherwise the torque obtained from the look up table of theelectric motor should be added too.

Figure 4.11: CVT control, power commanded

Running this model can show how the model follows a drive cycle. For thesimulation the USA drive cycle FTP-Highway is used. In figure 4.13 the resultswill be shown of the power commanded CVT model.

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Figure 4.12: CVT model with drive cycle

Figure 4.13: Results CVT simulation, commanding power

It’s clear that the actual car speed is close to the desired speed. Only at acouple spots a significant error can be noticed. Especially at the end a big errorcan be seen but this can be easily explained. Braking in this model is onlydone by the electric motor. When this motor reaches its maximum negativetorque there will be a lack of breaking torque. In the figure can be seen thatthe electric motor reaches its maximum of -240 Nm a couple of times. Thishappens at the end too. In a real car additional torque will be applied by thedisc brakes. Of course it’s possible to implement this in the model but that’snot done yet. Another thing that has to be explained is the fact that R goesfast to overdrive. This explanation is also an easy one. Driving the engine onthe IOL means that a high torque is delivered. The power required to drive the

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car at a constant speed isn’t that high. This means that the engine speed hasto be low not to exceed the power request. This results in a low value of thegear ratio (overdrive). At the start of the driving cycle only the electric motoris working. When the car exceeds a certain speed the engine fires up and thetorque of the electric motor decreases. This control strategy makes the enginerun much more efficient than it does in a conventional car. So, IOL trackingand the all electric range makes this car much more fuel efficient than the stockvehicle. The model shown only represents the hybrid mode of the car.

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Chapter 5

Prius engine

Where conventional cars get all their power form their internal combustionengine, the engine in a hybrid electric car is assisted by an electric motor. Thisfact makes it possible to use a smaller engine in such a vehicle. The goal ofbuilding this car, as mentioned before, is increasing fuel economy, reducingemissions and maintain or increase performance. The engine used is chosen dueto a couple of reasons: High thermal efficiency, relatively low emissions and itscompatibility with Ethanol (E85). The prius engine differs from a conventionalengine at the thermodynamic cycle: It runs on an Atkinson cycle. This cycleprovides higher thermal efficiency, lower emissions with the disadvantage oflosing power. In a hybrid configuration this can be compensated by an electricmotor.

To run an engine on the Atkinson cycle the camshafts have to be adjusted. Thishas to be done in such a way that the intake valve is opened longer. This allowsintake air to flow back into the intake manifold. The effective compressionratio will be reduced, so the expansion ratio will exceed the compression ratio.A high expansion ratio allows a long powerstroke, so there is more time forexpansion of the combustion gasses and less heat is wasted. The peak thermalefficiency increases from an average of 25 for the conventional engine to 37 forthe Atkinson engine.

When opening the cam cover an obvious difference can be noticed between thecams for the intake valves and for the outlet valves. The cams for the intakevalves are less ’sharp’.

5.1 Why using ethanol

Nowadays people concern more and more about green house gas emissions. Tomeasure the amount of green house gasses emitted the following index is used:

GHGI = CO2 + 21 ∗ CH4 + 310 ∗N2O (5.1)

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’The Greenhouse Gasses, Regulated Emissions, and Energy use in Transporta-tion (GREET 1.5a) model was used to verify that the use of E85 in Trinitywould reduce greenhouse gas emissions by 43 percent compared to a conven-tional vehicle fueled by gasoline [Sha07]. CH4 and N2O can be controlled withafter treatment, using a catalyst. Unfortunately this will not work for CO2, butthe use of ethanol instead of gasoline will reduce the CO2 emission considerably.

Another advantage of using ethanol is the higher octane number rating. Becauseof the better knock resistant ethanol compression ratio can be increased, sooutput power increases too.

Using ethanol means that the gas milage will be lower due to differences inlower heating values. The lower heating value of gasoline is 31.5 MJ/L, wherethe lower heating value of E85 is 22.6 MJ/L. This is 28 percent lower. Toinject the right amount of E85 the air-fuel ratios of gasoline and E85 have tobe compared. The air-fuel ratio of gasoline is 14.7, the air-fuel ratio of E85 is10. This means that for every liter gasoline 1.47 liter E85 has to be injected toburn a stoichiometric mixture. Injecting this amount of E85 will increase theengine power with approximately 5 percent.

5.2 Adjustments on the engine

Some minor adjustments on the engine had to be made to make the engineand its fuel system compatible with E85. Ethanol is highly corrosive. A newE85 compatible fuel tank was bought. All the fuel lines are made of stainlesssteel and the fuel pump is a special pump for alcohols which can provide aconstant pressure of 60 psi. This pressure is necessary to vaporize the ethanol.Furthermore the injector O-rings wre replaced by neoprene rubber O-rings.

These adjustments were the only advices from the dealership. Other modifica-tions made on the engine will be presented later, because these have nothing todo with the fuel change.

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Chapter 6

Dynamometer test stand

The hybrid electric vehicle lab already had a testrig with an eddycurrent dy-namometer but a more heavy duty dynamometer was desirable. Two majorprojects have to be done in the near future with this dynamometer: Tuning aPrius engine for ethanol combustion and test a pre-transmission parallel hybriddrivetrain with an inline CVT. The goal of the second project is to test thecontrols for this drivetrain. At this moment the team is integrating the samedrivetrain in Sequoia, another car of Team Fate. This project requires a moreheavy duty dynamometer, while the Prius engine has a maximum power of 59kw and a maximum torque of 111 Nm. For the permanent parts of the dy-namometer test stand everything had to be designed for the maximum torquethe dynamometer can handle.

In the first place the dynamometer will be used for tuning the prius engine.During competition the car was driving well but the engine was not tuned yetfor E85. The power of this hybrid design is to run the engine constantly onits ideal operating line. The purpose of this test stand is to obtain 2 figures:Throttle position to torque and an engine map. This will provide the necessaryinformation to control the drivetrain in such a way that the engine will alwaysrun on the IOL.

To get the test stand operational a lot of things had to be done. These thingsare described in the next paragraphs.

6.1 Brackets and shafts

Several brackets and shafts had to be made. The permanent parts had to bedesigned for the maximum torque the dynamometer can handle. A decisionwas made to couple the dynamometer and the engine with a double U-joint.This joint can compensate for misalignment in horizontal and vertical direction.For the project with the CVT drivetrain there was already a male spline shaftwith a flange which was made to connect to the U-joint. This mail spline shaftconnects to the output shaft of the CVT. This part could be used for the Prius

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engine project too: A female spline with a flange was made. This flange canconnect to the flywheel. Now only a connection between de dynamometer andthe U-joint had to be made. In the next paragraphs each part made will bediscussed. But first some analyses were done on the shafts which were alreadyin the lab.

The U-joint can compensate for misalignment of several millimeters. The di-mensions of this shaft are shown in the next picture.

Figure 6.1: Dimension of the double U-joint

In report [Sch05] is written about the male spline shaft. The spline, shown infigure 6.2 is made of steel 4340 and has a key connection on the other side.Two calculations show that this shaft and key connection are strong enough towithstand the maximum torque which can be applied to the dynamometer.

Figure 6.2: The spline shaft with key connection

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The governing equation for maximum torque applied on the shaft before failureoccurs is as follows:

Tmax,shaft =πd3

16

√3

3Sy (6.1)

Solving this equation with the right dimensions and the right material propertiesof the shaft gives a maximum torque of 1063 Nm.

The governing equation for the maximum allowable torque on the key is asfollows:

Tmax,key =

√3

3 SyLd2

8(6.2)

Solving this equation results in a maximum torque of 1354 Nm. Both valuesare higher than the maximum torque the dynamometer can load to the system:948 Nm. In fact this torque will never be reached because the first project cannever deliver this amount of torque and the second project’s purpose is to verifythe controls. Such a high torque is not necessary for this purpose.

After this analyses the brackets and other shafts had to be made.

6.1.1 Engine mounting brackets

The engine had to be rigidly mounted to the stand. Only one stock mountingpoint was on the back of the engine. This is one of the points where the enginewill be mounted to the stand. But first the front of the engine will be mountedto a bracket. This bracket had to be designed to withstand the most torquethe engine produces. Out of a big 1/4” steel plate from the scrap pile a circlewith some kind of wings at two sides was cut with the cutting torch. In thecircle a hole was cut with the diameter of the flywheel plus a little clearance.On the circle 8 holes were drilled to mount to the engine. To locate the centersof the holes a drawing with the exact locations of the holes was plotted andattached to the material. This drawing is shown in appendix D. Under thetwo wings little plates with two holes were welded. These plates were mountedwith 2 bolts to already existing brackets, consisting rubber damping mounts.See figure 6.3.

Considering the maximum torque of 111 Nm the maximum stress in the boltsof the bracket can be calculated. Information about maximum tensile strengthof bolts was found at www.mcmaster.com. The used bolts have a minimumtensile strength of 120.00 [psi], 827.4 [MPa]. In this case the shear stress isthe stress to be analyzed. The maximum tolerable force can be calculated asfollowing [Gro05]:

Fmax = 0.7σ2A (6.3)

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Figure 6.3: Front engine mounting bracket

A =π

4D2 (6.4)

Where A is 7.85e-5 m2, the maximum force on one bolt is 90 kN.

The distance from the shaft to the bolts is 168 mm. At the maximum torque theforce on the radius of the bolts is just 655 N. This will not cause any problem.Because of the chosen thickness of the steel there will be no problem at all withstresses in this bracket.

At the rear of the engine another bracket was made. The most important goalfor this bracket is to just carry the engine: Adding a vertical force. Becausethere also will be a little bit of torsion, bars were mounted on 45 degrees to themain pilar. All the parts are made of steel, rectangular profile. The fabricationof this part was done when the engine was already mounted to the front mount.The rear was carried by a lift. The bracket is shown figure 6.4.

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Figure 6.4: Rear engine mounting bracket

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6.1.2 Dynamometer mounting brackets

Maximum torque applied on the dynamometer could be 700 foot pound, what isequal to 948 Nm. With this knowledge brackets could be designed. A decisionwas made to make 3 separate brackets. Two of these are the same and weremounted to a quarter inch steel plate which was mounted to the blue disk onthe dynamometer. See figure 6.5. Fortunately there were two old steel bracketsavailable which could be used after some little grinding work. The other oneis mounted under the dynamometer. This one has to carry a part of the ownweight of the dynamometer. The other 2 brackets are most important. Togetherthey must withstand the torque applied on the dynamometer. The quarter inchplate was mounted with 4 bolts to the blue disk. To be sure the brackets, thebolts and especially the metal around the bolts are strong enough some stressanalyses had to be done.

The radius where the torque applies on the bolts on the steel plate is 0.12 [m]for the connection to the dyno. When the total force will apply on just onebolt the resulting force on that bolt will be 7.9 [kN]. The maximum force canbe calculated similar as in the previous paragraph. This time A = 5.1e-4, whatresults in a maximum force of 590 kN. These bolts will not give a problem, sothe bolts on the brackets which are further from the axis will not give problemseither.

The brackets where the plate is mounted at are just 3.5 mm thick. The areawhere the force of the bolts is working at is determined as follows:

A =13∗ t ∗ circumference (6.5)

Here t is the thickness of the material of the bracket. A=4.4e-5. Stress is theforce divided by the surface. On this radius the force is 3.8 kN. This will resultin a stress of 86 MPa. This stress will be reached in case of only one loadedbolt. The yield stress of steel is 400 [MPa] so this may not cause any problems.A picture of the dynamometer mounting is shown below.

The bracket to carry the own weight of the dynamometer is also made of steel.

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Figure 6.5: Mounting dynamometer

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6.1.3 Dynamometer adaptor plate

Next to the brackets the connections between the flywheel and the dynamometerhad to be made. First an adaptor was made to connect the dynamometer tothe U-joint. At the dynamometer side it connects to a surface with 8 threadedholes. At the U-joint side it has to connect to a surface with 4 through holes.The first design consisted a shaft with a flange on both sides. There were twoways to machine this part: in one part or 3 separate parts. Machining it fromone part on the lathe will result in wasting a lot of material and will take a longtime. First machining 3 separate parts and weld them together was the otherpossibility. Probably this is the cheapest and the fastest way but concentricitywill be an issue. Welding the parts exactly concentric will be almost impossible.A new design was made: Two separate disks which should bolt together. Onepiece has the 8 holes for the connection to the dynamometer and the otherone the 4 holes for the connection to the U-joint. Both pieces are one inchthick. In both pieces a circular pocket of half an inch was made. This is thearea where the bolts will come. On a bigger radius 4 holes were made in bothpieces. These holes make it possible to bolt the pieces together. The heads ofthe bolts which connect to the dynamometer or ujoint are inside the piece. Toobtain perfect concentricity connecting the parts a little step in thickness wasmade. The first piece has a thickness of, from outer to inner diameter, 1 inchto 0.9 inch to 0.5 inch. The other piece will will have a thickness of, from outerto inner diameter, 1 inch, 1.1 inch and 0,5 inch. A potential misalignment isprevented. All the holes are made on the mill. With a special indicator thecenter of both parts could be located. A little program was written to drill theholes at the right positions. Drawings of both parts are shown in 6.6 and 6.7.A picture of the parts bolted down to the dynamometer and the U-joint can beseen in the previous paragraph.

Figure 6.6: Dynamometer adaptor part 1

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Figure 6.7: Dynamometer adaptor part 2

Each bolt can withstand a force of 147 kN. Dividing the maximum force bythe radius shows that the maximum force will be 22 kN so the bolts are strongenough.

6.1.4 Flywheel adaptor shaft

Only one mechanical part lasts now. The connection between the flywheel anda male spline. The flywheel is bolted to the crankshaft with 6 bolts. This isthe place where the shaft has to connect to. A flange of 3/8 inch thick will bebolted down to the flywheel. The other end consists of a female spline, made byGear Industries. Only the 6 holes of this part are made in the Student MachineShop. These holes were also drilled on the mill by writing a little program. Adrawing and a picture are shown in the figures 6.8 and 6.9. In the drawing thespline is not shown, but the manufacturer used the male spline to make thisone.

This shaft completes the connection between the engine and the dynamometer.Unfortunately the bolts to connect the shaft to the flywheel didn’t arrive beforeleaving the lab, so a picture with everything bolted together could not be made.

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Figure 6.8: Flywheel adaptor shaft

Figure 6.9: Picture of the flywheel adaptor shaft connected to the splineshaftfor the cvt

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6.2 Engine

6.2.1 Engine controls

In Trinity the engine is controlled by a Mototron engine controller with 128pins. This controller was selected because of the robust automotive productionand the possibility to produce the control algorithms with Simulink. Thesecontrols can run on hardware with a real time operating system. This allowsstudents to develop their controls in a simulation environment. One of the toolsof MotoHawk will automatically generate a code from Simulink models whichthe hardware controller uses. The engine controller in Trinity takes care ofall the necessary engine controls and some accessories like cooling pumps. Intrinity an electric pump is used for the engine cooling but for the dynostandthe stock waterpump will be used. The mototron controller makes it possibleto control the engine for ethanol combustion.

As said, the engine controller takes care of all the engine controls, which meansreading several sensors and actuating several systems. In appendix C the con-troller is shown with all its in and output ports and the wiring to the sensors,coils and fuelinjectors. For the dynostand a total new wiring harness was madeto control this engine. The wire diagram was already available from the car,only some minor changes were made. The controller was placed close to theengine. From here necessary wires go to the engine, battery and to the out-side of the dynocell. The wiring going outside of the dynocell are the wires forthe keyswitch, CAN (communication area network), serial, fuelpump and thestartermotor. This allows to start the engine without being in the dynocell.When the engine is running nobody is supposed to be there.

Due to the use of this standard engine controller some adaptions had to be madeon the engine. The Mototron controller is adjustable, but at some levels in thesoftware it’s impossible to change the standard controller. Because of this a newencoder plate for the crankshaft position sensor was installed. Mototron onlysupport a couple of these encoder plates, so a right encoder plate was orderedfrom Saab. The encoder plate was mounted to the crankshaft pulley with anadaptor plate which was made on the lathe. The material used is aluminum,so it doesn’t weight too much. A picture of this adaptor plate and the newencoder plate is shown in figure 6.10. By making a little step in height withthe diameter of the hole in the encoder plate concentricity was ensured. Theencoder plate and the adaptor were bolted down by 4 bolts and this togetherwas bolted down by the bolt of the crankshaft. This allowed to change theangular positioning of the encoder plate by releasing the crankshaft bolt.

For the same reason as the encoder plate the encoder for the camshaft positionhad to change. By taking of the camcover 3 encoder pins can be seen. Thishad to change into one pin. The middle one was the necessary one, the othertwo were pressed out. Figure 6.11 shows the original camshaft where are thepins are still there.

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Figure 6.10: Encoder plate withe the adaptor plate

Figure 6.11: Encoder pins on camshaft

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6.2.2 Engine cooling

Engine cooling is done by the stock water pump. Where usually a radiator isused to cool the engine coolant, now a heat dump will be used. This heatdumpconsists of a reservoir, a waterinlet from the sink, a wateroutlet to the drainand an inlet and outlet for the water circulation through the engine. The watertemperature in the reservoir is measured and when the temperature gets tohigh water from the reservoir goes into the drain and cold water from the sinkwill flow into the reservoir. The advantage of this system is that the smalldynocell will not be heated. In this case it’s actually necessary because thecooling facilities in the small room are not sufficient.

The heatdump is shown in figure 6.12.

Figure 6.12: Heatdump

6.3 Dynamometer

The hybrid electric vehicle lab obtained an old ’Go Power Systems’ waterbrakedynamometer. With this waterbrake a solenoid valve and a display/controlconsole came. Unfortunately this console was so old that is was impossible toorder the products to get it operational. The specifications are comparable to

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a newer version from Go Power Systems: The 516 Series.

Torque 700 LB-Ft or 948 NmPower 900 HPRPM 7500 Peak and 5000 Cont.Rotation CW, CCWAlloy Material AluminumWater Requirements 3/4” - 1.0 line, 35 psi, .06 GPM/HPWeight 95 LBTorque Transducer Hydraulic

The control systems Go Power sells are very expensive so an own controllerhad to be made and used. Because the dynamometer hadn’t been used fora long time a load cell refill kit and new load cell diaphragms were boughtand installed. It was decided not to buy a new display console because themeasurements can be displayed on a pc as well.

6.3.1 Hydraulic system of the dynamometer

The last part to get this system operational is building the hydraulic systemsfor the dynamometer and control it. There are two seperate hydraulic systemnecessary to get the water brake to run. The first system is important for dataacquisition. Next to a tachometer there are two load cells. These two cellstogether apply pressure which represents the torque applied to the dynamome-ter. A hose from both of the load cells come together in a tee fitting. At theother end of the tee fitting a hose coupled to a pressure transducer is installed.This pressure indicates the amount of torque on the waterbrake. The systemis designed so that one psi represents one lb-ft. The pressure transducer forthis system is ordered from the company Digikey. The specifications of thistransducer are in the table below.

Pressure range 1000 psiPressure unit psiElectrical output 0.5 to 4.5 VdcPressure port 1.4 inch NPTElectrical connection 2ft cable

The pressure range is chosen so that it just exceeds the maximum pressure theload cells can apply. The electrical output is chosen to give the right output forthe used Mototron controller. At the moment fluid flows through flexible hosesbut these will be substituted by stainless steel brake lines. These brake lineswill be flared and a NPT fitting will be attached so it fits the 1/4 inch NPTfitting of the transducer.

Another hydraulic system has to take care of the right water flow into the dy-namometer. The water level in the brake determines how much power can beabsorbed. To control this input flow a pump, valve and a reservoir are necessary.

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Output flow control is not necessary. Considering the water requirements of thedynamometer a pump was bought. Because all small commercial pumps meet-ing this requirements were very expensive an oversized lawn pump is boughtfrom Wayne pumps. The specifications of this pump are shown in the tablebelow.

Continuous duty pump has 1 1/2 HP 230 Volt, single stage motorDual voltage available (115/230), factory wired for 230 voltsMotor Speed: 3450 RPMCast iron pump housing stainless steel shaft for durabilityMaximum Suction Lift: 25ft.Max PSI: 50 PSI2in. NPT suction port1 1/2in. NPT discharge portMoves up to 4790 GPH @10 PSI 5ft. lift and 2390 GPH @ 30 PSI 25ft. liftGlass reinforced thermoplastic impeller and diffuser for corrosion-resistanceCeramic/carbon-faced seal for long life

Besides a pump a reservoir of 9 gallon was ordered. Unfortunately this part wasnot delivered before leaving, so the connection between different componentswith pipes and hose hasn’t been made yet. The first design of how the differentcomponents have to connect to each other is shown in figure 6.13.

Figure 6.13: Dynamometer hydraulics

As mentioned before the cooling in the dyno cell is not sufficient. This is thereason for not using a radiator, so the principle of the heatdump will be used

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again. A temperature sensor will monitor the water temperature at the outputof the dynamometer and when this becomes to high cold water will flow intothe reservoir and push out warmer water, which goes directly to the drain. Toregulate the inlet flow a solenoid valve from the company Pulsecooling will beused. This valve receives a constant 12VDC signal. Grounding one of the pinswill open the valve.

6.3.2 Controlling the dynamometer

As said the dynamometer absorbs an amount of power depending on the waterlevel in it. The water level changes as a consequence of difference between theinput and the output flow. This can be done by controlling the input flow.The torque load of the waterbrake is correct when the rotational speed staysconstant. To control this inlet flow a solenoid valve will be used. A proportionalflow valve would be more ideally but the solenoid valve was delivered togetherwith the dynamometer, so it’s a cost saving issue. There will be a constantpressure from the pump. The valve will be opened if necessary. Pulses will besent to the valve to achieve an as good as possible constant flow. Dependenton the required flow the valve will be opened for a longer period. Changing thelength of the pulses will be done according to the rotational speed. Just likewith the engine, a Mototron controller will be used. This time it will be a 48pin controller of Mototron. The reason for using a second controller is that thewaterbrake will be permanent and several projects will use this dynamometer.

6.4 Results

Unfortunately there was not enough time to finish this project. This meansthere are no results to show, but a lot of work has already been done. Theengine is ready to start if all the wires which are already made will be connectedto the Mototron controller. The mechanical connection between the engineand the dynamometer is completed and all the necessary brackets are made.Completing the hydraulic system for the water supply is all that is left to do.In the near future the test stand will be operational, so an engine map and athrottle-torque curve can be produced.

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Chapter 7

Conclusion

The report shows that a lot of work has been done but that the actual assign-ment is not finished yet unfortunately. A lot of time and work went into thecompetition and not without good results. The team did not end up high atthe ranks, but that was not the main goal. A better fuel economy was achieved,with even more room left to improve. For better understanding of the drive-train a model of the CVT and its controls were made. The drivecycle can befollowed well, which shows that this control strategy can really work. Resultsclearly show how the internal combustion engine and front electric motor areworking together. The model can be extended to calculate fuel economy fordifferent drive cycles. Although the test stand is not finished yet, most of thework has been done. Brackets and shafts were made, all parts were ordered andthe engine is almost ready to be fired up. When the total hydraulic system ofthe dynamometer is hooked up, controls have to be written and then the standis ready to use.

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Appendix A

Symbols

η efficiency -T Torque Nmω angular velocity rad/sEb battery voltage VIb battery current ampsEoc open circuit voltage VIoc open circuit current ampsRb battery resistance ohmωds angular velocity drive shaft rad/sR cvt ratio -Te cvt input torque NmIe engine inertia kgm2

Ids drive shaft inertia kgm2

Trl torque road load NmRw wheel radius mfr rolling resistance coefficient -mv vehicle mass kgg gravitational acceleration m/s2

ρ mass density kg/m3

V 2v vehicle speed m/s

Cw air drag coefficient -A frontal area vehicle m2

a vehicle acceleration m/s2

Fmax maximum allowable force Nd diameter mSy yield stress Paσ stress PaL length mt thickness m

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Appendix B

Derivation of the accelerationof the drive shaft

Figure B.1: Schematic CVT drive train

Ieωe = Te − Tp (B.1)

Idsωds = Td − Tds (B.2)

ωds =Td − Tds

Ids=

Tpr − Tds

Ids(B.3)

ωds =(Te − Ieωe)r − Tds

Ids(B.4)

ωe = rωds (B.5)

ωe = ωdsr + ωdsr (B.6)

ωds =(Te − Ie(ωdsr + ωdsr))r − Tds

Ids(B.7)

(Ids + Ier2)ωds = Ter − Ierωdsr − Tds (B.8)

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ωds =Ter − Ierωdsr − Tds

(Ids + Ier2)(B.9)

ωds =Ter − Ieωer − Tds

(Ids + Ier2)(B.10)

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Appendix C

Engine harness

Figure C.1: Engine harness

*Some of the wires are not shown. This to keep the drawing readable. Color

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and pin on the Mototron are mentioned. Engine can fire up without a knockand oil pressure sensor but in the feature these will be added.

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Appendix D

Technical drawings

D.1 Dynamometer adaptor plate part 1

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Figure D.1: Technical drawing dynamometer adaptor plate part 1

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D.2 Dynamometer adaptor plate part 2

Figure D.2: Technical drawing dynamometer adaptor plate part 2

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D.3 Flywheel adaptor shaft

Figure D.3: Technical drawing flywheel adaptor shaft

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D.4 Encoder adaptor plate

Figure D.4: Technical drawing encoder adaptor plate

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D.5 Front engine

Figure D.5: Technical drawing holes front engine

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List of Figures

3.1 Stock Chevrolet Equinox 2005 . . . . . . . . . . . . . . . . . . . . 10

3.2 ”Plug in to the sun” . . . . . . . . . . . . . . . . . . . . . . . . . 10

4.1 Powertrain used in Trinity . . . . . . . . . . . . . . . . . . . . . . 11

4.2 Efficiency map electric motor . . . . . . . . . . . . . . . . . . . . 13

4.3 Electric diagram battery and motor . . . . . . . . . . . . . . . . 13

4.4 Efficiency map electric motor including battery losses . . . . . . 14

4.5 CVT chain by Gear Chain Industries . . . . . . . . . . . . . . . . 15

4.6 Hydraulic diagram cvt . . . . . . . . . . . . . . . . . . . . . . . . 16

4.7 Pipes and hoses for CVT . . . . . . . . . . . . . . . . . . . . . . 17

4.8 CVT model, commanding speed . . . . . . . . . . . . . . . . . . 18

4.9 Saturation of R and Rdot . . . . . . . . . . . . . . . . . . . . . . 19

4.10 Results CVT simulation, commanding speed . . . . . . . . . . . . 19

4.11 CVT control, power commanded . . . . . . . . . . . . . . . . . . 20

4.12 CVT model with drive cycle . . . . . . . . . . . . . . . . . . . . . 21

4.13 Results CVT simulation, commanding power . . . . . . . . . . . 21

6.1 Dimension of the double U-joint . . . . . . . . . . . . . . . . . . 26

6.2 The spline shaft with key connection . . . . . . . . . . . . . . . . 26

6.3 Front engine mounting bracket . . . . . . . . . . . . . . . . . . . 28

6.4 Rear engine mounting bracket . . . . . . . . . . . . . . . . . . . 29

6.5 Mounting dynamometer . . . . . . . . . . . . . . . . . . . . . . . 31

6.6 Dynamometer adaptor part 1 . . . . . . . . . . . . . . . . . . . . 32

6.7 Dynamometer adaptor part 2 . . . . . . . . . . . . . . . . . . . . 33

6.8 Flywheel adaptor shaft . . . . . . . . . . . . . . . . . . . . . . . . 34

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6.9 Picture of the flywheel adaptor shaft connected to the splineshaftfor the cvt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

6.10 Encoder plate withe the adaptor plate . . . . . . . . . . . . . . . 36

6.11 Encoder pins on camshaft . . . . . . . . . . . . . . . . . . . . . . 36

6.12 Heatdump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

6.13 Dynamometer hydraulics . . . . . . . . . . . . . . . . . . . . . . . 39

B.1 Schematic CVT drive train . . . . . . . . . . . . . . . . . . . . . 45

C.1 Engine harness . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

D.1 Technical drawing dynamometer adaptor plate part 1 . . . . . . 50

D.2 Technical drawing dynamometer adaptor plate part 2 . . . . . . 51

D.3 Technical drawing flywheel adaptor shaft . . . . . . . . . . . . . 52

D.4 Technical drawing encoder adaptor plate . . . . . . . . . . . . . . 53

D.5 Technical drawing holes front engine . . . . . . . . . . . . . . . . 54

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Bibliography

[Bro] A.W. Brown, J.v. Rooij, and A.A. Frank. The design of an inline gcichain cvt for large vehicles. Technical report, Brown Co., GCI andUCDavis.

[Gro05] M.P. Groover. Fundementals of Modern Manufacturing Material,Processes, and Systems, London: Prentice Hall International Editions.2005.

[Sch05] Niels Scheffer and Guus J.C.M. Arts. Realisation inline-cvt testrig.Internship report, UC Davis Hybrid Electric Vehicle Center, 2005.

[Sha07] Andrew Shabashevich, Douglas Saucedo, Terrence Williams, ChristianReif, Cuyler Lattoraca, Bryan Jungers, Beth Wietzel, Professor An-drew Frank, and Team Fate. Consumer ready plug-in hybrid electricvehicle. Technical report from competition, University of California,Davis, 2007.

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